The present invention relates to a light source unit and a projector system including the light source unit, and more particularly to a light source unit that is made smaller in size without reducing the utilization efficiency of light from a light source and a projector system including the light source unit.
Projector systems are such that light emitted from a light source unit is passed through a color wheel, is thereafter caused to enter a mirror tunnel so as to be made into light having a uniform luminous intensity distribution and is then projected on a screen while the quantity of light of each pixel is being changed over by a micro mirror device or a liquid crystal display element, so that an image is displayed on the screen.
As shown in FIG. 14, a light source unit 40 is made up of a light source 41 which emits light, a convex lens 42 disposed on an optical axis K for gathering light emitted from the light source 41 and a mirror tunnel 43 which light emerging from the convex lens 42 is made to enter to shine thereon (refer to Patent Document No. 1).
The light source 41 is made up of a reflector 44 and a lamp 45 inserted into the reflector 44. The lamp 45 is made up of a bulb 46 and electrode introducing portions 49, 49, and the bulb 46 is inserted so as to be positioned within the reflector 44. Note that the illustration of a color wheel is omitted in FIG. 14.
Here, part of the light that is emitted from the bulb 46 and is then reflected on an internal wall of the reflector 44 impinges on the electrode introducing portion 49, whereby the quantity of light is dampened. In addition, the convex lens 42 cannot sufficiently illuminate a light incident surface 43a of the mirror tunnel 43 with the light reflected by the reflector 44.
Due to this, the light source unit 40 needs to have a certain size or larger in order to secure a certain quantity of light, and hence, a projector system incorporating the light source unit 40 so enlarged tends to be enlarged, resulting in a problem that the projector system is not necessarily easy to carry and set.
While the light source unit is preferred to be small in so as to make the whole of the projector system small, it is a conventional idea that the lamp in the light source unit must have a certain size or larger so as to secure a necessary quantity of light.
[Patent Document No. 1] Japanese Unexamined Patent Publication No. 6-51401